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Today's Topic

Nothing can go faster than light, right? Einstein said so. But last week a group of researchers in Italy announced that they'd measured the speed of thousands of neutrinos (tiny, almost massless particles that were fired at their detector from the CERN particle physics lab 730 kilometers away) and found they were traveling slightly faster than light[2]. Is this the beginning of the end for Einstein's theory of relativity? Have the researchers simply made a mistake in their measurements? Or are the neutrinos, as some versions of string theory allow, taking a shortcut through a higher dimension and arriving in Italy in double-quick time?

Join us for a live chat on this page at 3 p.m. EDT on Thursday, 29 September, to discuss these and other questions with two experts in the field. You can leave your questions in the comments section below before the chat starts.

Alan Kostelecky is a theoretical physicist who studies the fundamental laws of nature. His publications span a broad range of topics in particle physics, gravitation, string theory, mathematical physics, and atomic physics. He pioneered the idea that tiny observable deviations from the laws of relativity could emerge from an underlying unified theory. His comprehensive theoretical description of relativity violations, called the standard-model extension (SME), has led to many new experimental tests of special and general relativity.

Alfons Weber

Alfons Weber is reader in particle physics at the University of Oxford and holds a joint appointment with the Rutherford Appleton Laboratory. He worked at the LEP collider at CERN before moving to the United Kingdom, where he is now working on the MINOS and T2K experiments.